Total Hip Replacement Research Articles

A non-intrusive reduced-order model for finite element analysis of implant positioning in total hip replacements.

Sophisticated high-fidelity simulations can predict bone mass density (BMD) changes around a hip implant after implantation. However, these models currently have high computational demands, rendering them impractical for clinical settings. Model order reduction techniques offer a remedy by enabling fast evaluations. In this work, a non-intrusive reduced-order model, combining proper orthogonal decomposition with radial basis function interpolation (POD-RBF), is established to predict BMD distributions for varying implant positions. A parameterised finite element mesh is morphed using Laplace's equation, which eliminates tedious remeshing and projection of the BMD results on a common mesh in the offline stage. In the online stage, the surrogate model can predict BMD distributions for new implant positions and the results are visualised on the parameterised reference mesh. The computational time for evaluating the final BMD distribution around a new implant position is reduced from minutes to milliseconds by the surrogate model compared to the high-fidelity model. The snapshot data, the surrogate model parameters and the accuracy of the surrogate model are analysed. The presented non-intrusive surrogate model paves the way for on-the-fly evaluations in clinical practice, offering a promising tool for planning and monitoring of total hip replacements.

COMPARISON OF ULTRASOUND-GUIDED LUMBAR ERECTOR SPINAE PLANE BLOCK AND TRANSMUSCULAR QUADRATUS LUMBORUM BLOCK FOR POST-OPERATIVE ANALGESIA IN TOTAL HIP REPLACEMENT SURGERIES: A PROSPECTIVE RANDOMIZED STUDY

Objectives: The objective of the study is to compare the efficacy of ultrasound-guided lumbar erector spinae plane block (ESPB) and transmuscular quadratus lumborum block (QLB) in providing post-operative analgesia for patients undergoing total hip replacement (THR) surgeries. Methods: This prospective, randomized, double-blind study compared the efficacy of ultrasound-guided lumbar ESPB and transmuscular QLB (QLB-t) for post-operative analgesia in THR surgeries. Ninety patients were randomized into three groups: ESPB, QLB, and a control group. Primary outcomes included the duration of analgesia, measured by numeric rating scale scores, and secondary outcomes assessed total analgesic consumption and the incidence of post-operative nausea and vomiting (PONV) within 24 h. For statistical purposes, p<0.05 was taken as statistically significant. Results: This study compared lumbar ESPB and QLB for post-operative analgesia in THR surgeries. At the 1st h, pain scores were significantly lower in the ESPB (1.30) and QLB (1.05) groups compared to the control group (2.15) (p<0.001). Tramadol consumption in the first 12 h was significantly lower in the ESPB (52.3 mg) and QLB (50.1 mg) groups compared to the control group (135.20 mg) (p<0.001). PONV was absent in 60% of ESPB and 63% of QLB patients, compared to only 33% in the control group (p=0.038). Conclusion: Lumbar-ESPB and QLB-t blocks effectively reduce post-operative pain and analgesic requirements in THR surgeries, showing comparable benefits. Both techniques also lower the incidence of PONV.

Combined Lumbar and Sacral Plexus Block in an Elderly Patient with Coronary Artery Disease for Unilateral Total Hip Replacement as a Sole Anaesthetic

Combined Lumbar and Sacral Plexus Block in an Elderly Patient with Coronary Artery Disease for Unilateral Total Hip Replacement as a Sole Anaesthetic

Evaluation of three acetabular measurement methods for total hip replacement in dogs.

To compare three measurement methods for acetabular sizing and evaluate the influence of osteoarthritis (OA) on the accuracy of measurements. Observational study. Radiographic images of 73 hip joints from 60 dogs with cementless cups. Radiographs were anonymized and measured independently by three observers. One observer measured 12 sets of radiographs three times. A best-fit acetabular circle (AC) and cranial-caudal acetabular line (AL) were measured on ventral-dorsal (VD) radiographic view and open leg lateral (OLL) view. A best-fit femoral head circle (FHC) was measured on VD, OLL, and craniocaudal horizontal beam (CCHB) views. Two observers scored the OA in each hip joint. Intra- and interobserver consistency and repeatability and bias relative to implanted cup size were calculated and analyzed. Intraobserver consistency and repeatability were excellent for all measurements. Interobserver consistency was excellent (ICC > 0.9) for ACVD and ACOLL and was good (0.75 < ICC ≤ 0.9) for all other methods. Bias was small for AC and AL measurements (range, -0.46 to 0.45 mm) and large for FHC measurements (-3.58 to -2.42 mm). OA score significantly influenced bias for all acetabular measurement methods (p < 0.05). All acetabular measurement methods were highly consistent within an observer. Interobserver consistency was highest for ACVD and ACOLL. FHC measurements underestimated cup size. Higher OA scores decreased the accuracy of all acetabular measurement methods. Superimposing a circle on the acetabulum seen on VD radiographic view accurately measures the acetabulum before cementless cup placement.

Radiological Spinopelvic Parameters Can Be Risk Factors for Early Total Hip Replacement After Spine Fusion.

Interest in the correlation between the spinopelvic complex and its radiographic parameters in early total hip arthroplasty has been increasing. This study investigated whether radiological spinopelvic parameters are risk factors for early total hip replacement (THR) within 1 year of spinal fusion surgery. The primary research question focused on identifying specific spinopelvic changes that may lead to early THR. We retrospectively analyzed patients who underwent lumbar spinal fusion between 2016 and 2021. The patients were divided into 2 groups: patients who underwent early THR (n = 35) and patients who did not (n = 213). Spinopelvic parameters, including pelvic incidence (PI), sacral slope (SS), pelvic tilt, lumbar lordosis, thoracolumbar kyphosis (TLK), sagittal vertical axis, and thoracic kyphosis (TK), were measured before and after surgery. The statistical analyses included inverse probability of treatment weighting, independent t tests, χ 2 tests, and logistic regression analyses. A total of 248 patients were included in the study. The pre- and postoperative TLK and TK angles were significantly smaller in the early THR group than in the late THR group. Increases in the PI and SS after surgery were significant risk factors. The use of interbody fusion techniques was associated with a higher rate of early THR. The difference in the PI minus lumbar lordosis before and after surgery was also significantly correlated with early THR. Abnormal spinopelvic parameters, especially reduced TLK and TK angles and increased PI and SS, are risk factors for early THR. Changes in spinopelvic parameters can lead to rapid hip joint destruction, which highlights the need for careful preoperative evaluation and postoperative monitoring of patients to prevent early THR.

Revision of Hip Luxation in a Canine Total Hip Replacement Caused by a Greater Trochanteric Fracture Secondary to an Inflammatory Granuloma.

A hip luxation 3 years following a cementless total hip replacement was diagnosed in a 4.7-year-old neutered male Lagotto Romagnolo that presented with a non-weight-bearing left pelvic limb lameness. Orthogonal radiographs revealed a left hip luxation and an osteolytic fracture of the greater trochanter. A mass consistent with an inflammatory granuloma was identified on preoperative computed tomography scan. Surgical revision consisted of granuloma excision, replacement of the loose acetabular cup, and repair of the femoral fracture with a locking plate. Fracture biology was augmented with the use of recombinant human bone morphogenetic protein 2 (rhBMP2) impregnated collagen sponge applied around the acetabulum and femoral fracture site. Osteointegration of the prosthetics and fracture healing were documented within 3 months of revision. Long-term follow-up at 3 years postrevision showed normal limb usage and no further evidence of total hip replacement complication.

The association of bearing surface materials with the risk of revision following primary total hip replacement: A cohort analysis of 1,026,481 hip replacements from the National Joint Registry.

The risk of re-operation, otherwise known as revision, following primary hip replacement depends in part on the prosthesis implant materials used. Current performance evidences are based on a broad categorisation grouping together different materials with potentially varying revision risks. We investigated the revision rate of primary total hip replacement (THR) reported in the National Joint Registry by specific types of bearing surfaces used. We analysed THR procedures across all orthopaedic units in England and Wales. All patients who received a primary THR between 2003 and 2019 in the public and private sectors were included. We investigated the all-cause and indication-specific risks of revision using flexible parametric survival analyses to estimate adjusted hazard ratios (HRs). We identified primary THRs with heads and monobloc cups or modular acetabular component THRs with head and shell/liner combinations. A total of 1,026,481 primary THRs were analysed (Monobloc: n = 378,979 and Modular: n = 647,502) with 20,869 (2%) of these primary THRs subsequently undergoing a revision episode (Monobloc: n = 7,381 and Modular: n = 13,488). For monobloc implants, compared to implants with a cobalt chrome head and highly crosslinked polyethylene (HCLPE) cup, the all-cause risk of revision for monobloc acetabular implant was higher for patients with cobalt chrome (hazard rate at 10 years after surgery: 1.28 95% confidence intervals [1.10, 1.48]) or stainless steel head (1.18 [1.02, 1.36]) and non-HCLPE cup. The risk of revision was lower for patients with a delta ceramic head and HCLPE cup implant, at any postoperative period (1.18 [1.02, 1.36]). For modular implants, compared to patients with a cobalt chrome head and HCLPE liner primary THR, the all-cause risk of revision for modular acetabular implant varied non-constantly. THRs with a delta ceramic (0.79 [0.73, 0.85]) or oxidised zirconium (0.65 [0.55, 0.77]) head and HCLPE liner had a lower risk of revision throughout the entire postoperative period. Similar results were found when investigating the indication-specific risks of revision for both the monobloc and modular acetabular implants. While this large, nonselective analysis is the first to adjust for numerous characteristics collected in the registry, residual confounding cannot be rule out. Prosthesis revision is influenced by the prosthesis materials used in the primary procedure with the lowest risk for implants with delta ceramic or oxidised zirconium head and an HCLPE liner/cup. Further work is required to determine the association of implant bearing materials with the risk of rehospitalisation, re-operation other than revision, mortality, and the cost-effectiveness of these materials.

Toxicity Risk from Hip implant CoCrMo Particles: The Impact of Dynamic Flow Rate on Neuronal cells in Microfluidic systems

In patients with total hip replacements (THRs), wear products in the form of nanoparticles and ions are released, especially around implant failure. In this study, we use N2a cells, a neuroblastoma cell line, to evaluate the effects of different flow rates on neuronal toxicity amidst exposure to CoCrMo particles. We hypothesized that increasing flow rates would increase N2a cell viability and decrease N2a cell-degradation products (DPs) toxicity. We conducted four 24-hour experiments, each with four flow rate conditions, 0, 50, 100, and 200 uL/min, based on the physiological shear stress of the vessels in the human body, to evaluate cell viability, cell morphology, and cell-DPs interaction. Steps included microfluidic channel preparation, N2a cell culturing, CoCrMo particle acquisition, microfluidic system assembly, and dynamic flow neurotoxicity evaluation, which included video microscopy, AlamarBlue, live/dead imaging, DAPI, and ROS assay. The results suggest that fewer neurotoxic reactions and greater viability at higher flow rates supported our hypothesis, although the full range of viable flow rates is yet to be studied. While cell-particle interaction is complex and dynamic, flow rate did modulate toxicity, viability, morphology, and growth environment. The microfluidic system should continue to be developed to study toxicology aspects of implants by simulating in vivo conditions more accurately.

No Difference in Outcomes, Complications, or Revision Rate for Obese vs. Nonobese Patients Following Hip Resurfacing Arthroplasty: A Systematic Review and Meta-Analysis.

Hip resurfacing arthroplasty (HRA) offers numerous benefits over total hip replacements such as increased preservation of natural bone, improved range of motion, and lower dislocation risks. However, patient selection is crucial, with factors such as bone quality, activity level, and body mass index (BMI) playing significant roles. Obesity in particular poses challenges, potentially increasing mechanical load on the joint, complicating surgical techniques, and affecting both immediate and long-term outcomes. The aim of this systematic review was to evaluate outcomes of HRA in obese vs. nonobese patients to determine if obesity should be considered a contraindication to HRA or if similar treatment approaches can be applied. A literature search was conducted using PubMed, Embase, and Scopus databases with specific search terms related to HRA and obesity. Articles were screened by title and abstract, followed by full-text review. Data extraction focused on demographic and study variables such as sex, age, BMI, complication and revision rates, and patient-reported outcomes. A meta-analysis was performed using a random-effects model to compare University of California Los Angeles (UCLA) scores, Harris hip scores, complication rates, and revision rates between obese and nonobese patients, with significance set at p < 0.05. From an initial pool of 39 articles, 4 met inclusion criteria, encompassing 1,385 patients. Analysis revealed a pooled mean age of 50.92 years and a complication rate of 9.83% in obese vs. 4.7% in nonobese patients. Revision rates were 1.15% for obese and 3.70% for nonobese patients. The difference in postoperative UCLA scores, complication rates, and revision rates were deemed not statistically significant. The comparability in patient-reported outcomes, complication rates, and revision rates between obese and nonobese cohorts suggests that although heightened vigilance and tailored approaches may be warranted in obese patients, obesity alone should not preclude patients from undergoing HRA. These findings advocate for a more nuanced approach to patient selection, emphasizing individualized assessment over generalized BMI cutoffs. Future HRA research should focus on long-term follow-up and larger cohort studies to further validate these results. Level III, systematic review of Level II and III studies. See Instructions for Authors for a complete description of levels of evidence.

Safety outcomes of tocilizumab and tofacitinib treatment for rheumatoid arthritis: Target trial emulation.

Biological disease-modifying antirheumatic drugs have been the primary treatment option for moderate to severe rheumatoid arthritis (RA) in Taiwan since 2010. Tocilizumab is an interleukin-6 receptor inhibitor, whereas tofacitinib is a Janus kinase inhibitor. The two medications were indicated to treat RA by direct and indirect inhibition of interleukin-6 cytokine. We compared the safety outcomes of tocilizumab and tofacitinib in patients with RA in real-world clinical settings, following the 7 key components of target trial emulation (TTE). The data source was the Taiwan National Health Insurance Research Database. Patients with RA between 2010 and 2018 were eligible and assigned to either tocilizumab or tofacitinib based on their first prescription of these two medications. The index date was set as the first prescription date of either study medication. Propensity score stabilized weighting (PSSW) was used to balance the characteristics between the two medication groups. The incidences of safety outcomes were all-cause mortality, cancer, coronary heart disease, stroke, venous thrombosis events, tuberculosis, joint replacement events, and herpes zoster infection. The intention-to-treat (ITT) effect was commenced from the index date until the study outcomes, independently, 3 years, withdrawal, or December 31, 2021, whichever occurred first. For the per-protocol (PP) effect, patients were required to maintain the same medical group during the entire follow-up period. A total of 2125 patients with RA who were prescribed tocilizumab (n = 844) or tofacitinib (n = 1281) were included in this study. The mean follow-up duration was 2.78 years in the tocilizumab group and 2.83 years in the tofacitinib group. For ITT, the sample sizes were 721 and 1196 for the tocilizumab and tofacitinib, respectively, after PSSW. A substantially lower incidence rate of herpes zoster infection (per 100 patient-years) was observed in the tocilizumab group (3.67) than in the tofacitinib group (7.61), with a hazard ratio of 0.48 (95%CI =0.37-0.63; p < .0001). All-cause mortality, cancer, coronary heart disease, stroke, total hip replacement, and tuberculosis were similar between the two medication groups. For PP, the sample sizes were 619 and 1085 for the tocilizumab and tofacitinib, respectively, after PSSW. The results of the PP analysis were similar to those of the ITT analysis. Tocilizumab and tofacitinib act along the same inflammatory pathway. A lower herpes zoster incident rate was observed in the tocilizumab group than in the tofacitinib group. The incidence rates of other safety concerns and mortality rates were comparable in both groups of patients with RA treated in real-world settings.

Effects of Small-Dose Esketamine on Postoperative Analgaesia and Sleep Quality in Patients with Total Hip Replacement.

To determine the effect of esketamine in patient-controlled analgaesia after hip replacement on postoperative pain and improve sleep quality in patients. Randomised double-blind study. Place and Duration of the Study: Department of Anaesthesiology, The First Affiliated Hospital of Guangxi Medical University, from March 2021 to May 2022. The research enrolled 72 patients who were subjected to unilateral complete hip replacement surgery utilising jointly administered universal and peripheral nerve-obstructing anaesthetics. A randomised numeric table method was used to allocate patients to either the F-D group (fentanyl combined with dexmedetomidine, n = 34) or the Es-D group (esketamine combined with dexmedetomidine, n = 38). The key outcome indicators included the time to first administration of rescue analgaesic, the dose of rescue analgaesics, and postoperative sleep quality. Baseline characteristics did not differ between the two groups. The time until postoperative analgaesic rescue medication was considerably shorter for those in the Es-D group (p <0.05). In addition, the Es-D group used significantly fewer rescue analgaesics (p = 0.01). The PSQI score and unpleasant responses (PONV, dizziness, nightmare) did not significantly differ between the two groups (p <0.05). Nevertheless, urine retention occurred in four patients in group F-D but not in group Es-D (p <0.05). Esketamine produced better analgaesia than fentanyl with fewer side effects after surgery. However, no improvement was observed in sleep quality. Arthroplasty, Postoperative analgaesia, Esketamine, Sleep quality, Patient-controlled analgaesia.

Cost-effective Skin Marking in Joint Replacement Surgery: A Comparative Study between Methylene Blue Ink and Commercially Available Skin Markers.

This study aimed to assess and compare the effectiveness and safety of methylene blue ink and commercially available surgical marker pens in pre-operative skin marking for joint replacement procedures. The objective was to evaluate the visibility of the surgical instruments during the operation and their influence on the occurrence of infections after the surgery, providing valuable information on the practical use and cost-effectiveness. This retrospective randomized study involved 150 total cases, which included knee replacements, total hip replacements, and hip hemiarthroplasty performed between 2020 and 2023. The same surgeon conducted all procedures, and the patients were randomly assigned to two groups: One marked with methylene blue ink and the other with a commercially available sterile marker pen. Limb preparation followed an identical protocol for both groups. The primary outcomes assessed were the visibility of markings at the end of the procedure and the incidence of post-operative infections. The visibility of markings was satisfactory in both groups, with the methylene blue group displaying more pronounced visibility. Importantly, there were no cases of post-operative infections or permanent tattooing attributed to either marking method. This study demonstrates that both methylene blue ink and commercially available surgical marker pens provide effective skin markings for surgical procedures without increasing the risk of post-operative infections or causing permanent tattooing. Methylene blue ink showed more evident marking post-procedure and ink form remains a cheaper alternative.

Effects of Small-Dose Esketamine on Postoperative Analgaesia and Sleep Quality in Patients with Total Hip Replacement.

To determine the effect of esketamine in patient-controlled analgaesia after hip replacement on postoperative pain and improve sleep quality in patients. Randomised double-blind study. Place and Duration of the Study: Department of Anaesthesiology, The First Affiliated Hospital of Guangxi Medical University, from March 2021 to May 2022. The research enrolled 72 patients who were subjected to unilateral complete hip replacement surgery utilising jointly administered universal and peripheral nerve-obstructing anaesthetics. A randomised numeric table method was used to allocate patients to either the F-D group (fentanyl combined with dexmedetomidine, n = 34) or the Es-D group (esketamine combined with dexmedetomidine, n = 38). The key outcome indicators included the time to first administration of rescue analgaesic, the dose of rescue analgaesics, and postoperative sleep quality. Baseline characteristics did not differ between the two groups. The time until postoperative analgaesic rescue medication was considerably shorter for those in the Es-D group (p <0.05). In addition, the Es-D group used significantly fewer rescue analgaesics (p = 0.01). The PSQI score and unpleasant responses (PONV, dizziness, nightmare) did not significantly differ between the two groups (p <0.05). Nevertheless, urine retention occurred in four patients in group F-D but not in group Es-D (p <0.05). Esketamine produced better analgaesia than fentanyl with fewer side effects after surgery. However, no improvement was observed in sleep quality. Arthroplasty, Postoperative analgaesia, Esketamine, Sleep quality, Patient-controlled analgaesia.

Patient Experiences with a Smartphone Application dedicated to postoperative recovery after Elective Arthroplasty

IntroductionIn the rapidly evolving landscape of digital health technologies, the widespread use of smartphones has paved the way for innovative applications designed to enhance healthcare experiences. This introduction underscores the global prevalence of smartphone users and their potential in healthcare, particularly exemplified by therapeutic apps such as the ‘PostOp’ smartphone application. Focused on postoperative support, this app prioritises user-friendly design, data recording, and adherence to national standards. The study aims to evaluate the app's success in achieving these objectives, highlighting its continuous improvement based on real user feedback and its potential impact on improving patient experiences and recovery processes. Methods and MaterialsA cohort of elective joint arthroplasty procedure patients at Kettering General Hospital (KGH), spanning a timeframe of one to 12 months post-surgery were surveyed over the telephone regarding their experience of the ‘Post Op’ smartphone utilising a custom, well-structured standardised questionnaire. ResultsThe study surveyed 42 consecutive patients who had undergone elective joint arthroplasty procedures at Kettering General Hospital, including 22 total hip replacement (THR) and 20 total knee replacement (TKR) patients. The respondents, with a median age of 66 years, provided overwhelmingly positive feedback about the ‘Post Op’ smartphone application. On a scale of 1 to 6, the mean ease-of-use score was 5.31, with only two THR patients providing lower scores due to difficulties with photography. However, the app's overall functionality, particularly in uploading photos, received a mean score of 4.78. Despite some technical issues, 97.6% of respondents would recommend the app, emphasising its positive impact on confidence in the recovery and reducing unnecessary healthcare visits. Narrative responses highlighted the app's simplicity, support, and prompt communication with healthcare teams. Overall, the feedback indicates a high level of satisfaction with the ‘Post Op’ application among elective arthroplasty patients, showcasing its potential benefits for postoperative care. ConclusionThe study provides valuable insights into the impact of the ‘Post Op’ smartphone application on postoperative care, acknowledging both its successes and areas for enhancement. Further research and iterative improvements are crucial for optimising patient experiences and ensuring the app aligns effectively with healthcare needs.

Management of Failed Fixation of Extracapsular Hip Fractures.

Background Extracapsular hip fractures are routinely treated with fixation, and the majority heal without complication. The fixation fails in a minority of cases, typically either by 'cutting out' of the superior femoral heador through breakage of the metalwork following non-union. In such cases, if operative treatment is thought appropriate, there are two major treatment options: revision fixation of the fractureor joint replacement surgery. Methods Medline on OvidSP was searched using relevant medical-specific subject headings (MeSH) and keywords. The inclusion criteria were: study regarding management of failed extracapsular hip fracture fixation (not osteoarthritis alone, following such surgery), mean age >60 years, comparative study of joint replacement vs. revision fixation. The search returned 1053 results, of which twowere relevant. Both studies were considered poor quality and neither study was randomised. Instead, outcomes from the current Hospital Trust were used instead through a prospectively generated trauma database. Results From the trauma database, 37 patients (mean age 81), of whom 21 had received cephalomedullary nails and the remainder dynamic hip screw (DHS), were identified. Fourteen patients underwent revision fixation (seven cephalomedullary nail; seven blade plate), while 23 underwent hip replacement (17 total hip replacement; six hemiarthroplasty). Although the difference did not reach statistical significance according to the log-rank test (p = 0.233), there is a trend towards lower re-operation rate following joint replacement, with the difference becoming apparent after over one year's follow-up. Conclusion Despite the quality of evidence, the default operation for failed extracapsular hip fracture fixation should be joint replacement, based on a likely lower re-operation rate and permitting immediate full-weight-bearing. In selected instances, particularly younger patients and those who can partially-weight-bear, revision fixation would still be considered. As the number of hip fractures continues to increase both within the UK and worldwide, we can expect to see more patients with previous failed fixations, and more evidence regarding the advantages and disadvantages of different treatment strategies is required.

Total Hip Replacement or Resistance Training for Severe Hip Osteoarthritis

BackgroundTotal hip replacement is routinely recommended for severe hip osteoarthritis, but data from randomized trials are lacking regarding comparison of the effectiveness of this procedure with that of nonsurgical treatment such as resistance training.MethodsWe conducted a multicenter, randomized, controlled trial to compare total hip replacement with resistance training in patients 50 years of age or older who had severe hip osteoarthritis and an indication for surgery. The primary outcome was the change in patient-reported hip pain and function from baseline to 6 months after the initiation of treatment, assessed with the use of the Oxford Hip Score (range, 0 to 48, with higher scores indicating less pain and better function). Safety was also assessed.ResultsA total of 109 patients (mean age, 67.6 years) were randomly assigned to total hip replacement (53 patients) or resistance training (56 patients). In an intention-to-treat analysis, the mean increase (indicating improvement) in the Oxford Hip Score was 15.9 points in patients assigned to total hip replacement and 4.5 points in patients assigned to resistance training (difference, 11.4 points; 95% confidence interval, 8.9 to 14.0; P<0.001). At 6 months, 5 patients (9%) who had been assigned to total hip replacement had not undergone surgery, and 12 patients (21%) who had been assigned to resistance training had undergone total hip replacement. The incidence of serious adverse events at 6 months was similar in the two groups; the majority of such events were known complications of total hip replacement.ConclusionsIn patients 50 years of age or older who had severe hip osteoarthritis and an indication for surgery, total hip replacement resulted in a clinically important, superior reduction in hip pain and improved hip function, as reported by patients, at 6 months as compared with resistance training. (Funded by the Danish Rheumatism Association and others; PROHIP ClinicalTrials.gov number, NCT04070027.)

Demographics of Total Hip and Knee Arthroplasty in Nepal: An Observational Study

Introduction: Hip and knee arthroplasty surgeries are essential for treating end-stage osteoarthritis, providing significant functional improvements. Despite a global rise in these procedures, Nepal lacks a National Joint Registry, resulting in a gap in tracking the exact number of surgeries, outcomes, and complications. This study aims to address this gap regarding the demographics of hip and knee arthroplasties in Nepal.Methods: An observational study was conducted after obtaining the ethical approval from the Nepal Health Research Council (Reference number: 2024/136) with data collected from prosthesis supplier. The study included all primary hip and knee arthroplasties performed in 2022 and 2023, excluding revision cases and those requiring mega prostheses. Data analysis was performed using Microsoft Excel for descriptive statistics.Results: There were a total of 1259 surgeries, 916 (72.77%) total knee replacements were performed, with a female predominance of 741 (81.42%) and a median age of 67 years(IQR: 62-71). There were 343 (27.23%) total hip replacements surgeries of which 200 (58.31%) were done in males. Most surgeries 1148 (91.18%) occurred within the Kathmandu Valley.Conclusions: Total knee arthroplasty accounted for the majority of cases, showing a predominance of female patients with the majority of surgeries in the capital city.

A Preliminary Study on Kinetic Analysis of Ground Reaction Force and Impulse During Gait in Patients With Total Hip Replacement and Implication for Rehabilitation.

There is little research done on ground reaction forces (GRF) in terms of 3D impulses after total hip replacement (THR). This study aimed to investigate the GRFs and 3D impulses in four sub-phases of stance during gait in the patients undergoing THR. A total of 10 pain-free THR patients and 10 healthy people were recruited. This is an observational and retrospective study. The gait data was collected between 2008 and 2014 and analyzed between 2020 and 2024. All the participants were included in the three-dimensional gait analysis. Gait parameters, phase durations, GRFs and impulses' key values during gait were calculated in four sub-phases of stance. Statistical comparisons were performed with generalized linear models including age, gender, body mass index and walking speed as interactive factors. It is found that (1) cadence, walking speed, stride length and step width in THR group were significantly decreased in compared with control group; (2) the THR decreased loading response duration in operative side and pre-swing duration in non-operative side compared with the control group, but the THR's two sides have similar duration proportions in sub-stance phases; (3) the THR group had lower GRFs than the control group in vertical direction but higher in the medial-lateral direction; (4) in operative side, the THR's impulses in loading response phase were lower than the control group in anterior-posterior direction, and (5) in non-operative side, the THR's impulse in pre-swing phase in anterior-posterior direction was higher than the control side. The THR group showed slower walking speeds than the control group. The reasons could be from the decreased impulse in loading response phase, the decreased 2nd peak of GRF and the decreased pre-swing impulse in vertical direction in operative side. Clinicians are suggested to consider the information provided when designing relevant rehabilitation exercises on the related muscles and functions.

Bilateral hip ochronosis, an unsuspected diagnosis in polyarticular pain: A case report

Alkaptonuria is a rare metabolic disorder characterized by the accumulation of homogentisic acid, leading to the deposition of blackish pigment in cartilage and soft tissue, known as ochronosis. This can mimic multiple joint pathologies and is a diagnosis of exclusion. We describe the case of a 52-year-old woman who had a total hip replacement after experiencing left hip pain for which oral medications were unable to provide relief. Unexpectedly, during the procedure, a blackish tissue was noticed. This led to a histological examination and the confirmation of the ochronosis diagnosis. The patient’s medical history revealed a number of malignancies, but no previous metabolic illness diagnoses. Subsequent follow-up revealed rapid-onset pain in other joints, leading to a similar diagnosis of polyarticular ochronosis in the right hip, knees, spine, and shoulders. This highlights how difficult it is to treat this condition. This case underscores the importance of considering ochronosis as a differential diagnosis in patients with chronic polyarticular pain. Current treatment consists of initial non-surgical measures, including physical therapy and analgesics. If there is no improvement, treatment would be joint arthroplasty. Awareness among orthopedic surgeons and histopathological examination of tissues is crucial for the accurate diagnosis and management of ochronosis.

Processing of Reduced Graphene Oxide Reinforced Ultra High Molecular Weight Polyethylene for Orthopedic Implants

Ultra-high molecular weight polyethylene (UHMWPE) has been used as a bearing material in total joint replacements due to its excellent mechanical properties and biocompatibility. The acetabular cup in total hip replacement and the tibial component in total knee replacement is widely fabricated from UHMWPE. The use of UHMWPE in total joint replacements is well established, and the goal is to improve its mechanical properties, wear resistance, and oxidation resistance. The quality and life span of the artificial joints can be further increased by enhancing the relevant mechanical properties of UHMWPE. The addition of filler material to UHMWPE is an effective way to enhance its relevant properties. In this study, relevant properties of UHMWPE were enhanced by incorporating an appropriate filler. Reduced Graphene Oxide (rGO) was selected as a filler material as it improves mechanical properties, wear resistance, toughness, and thermal stability. Graphene oxide (GO) was synthesized by Modified Hummer’s Method (MHM), and it was thermally reduced to obtain rGO. The synthesized GO was characterized by Fourier Transform Infrared spectroscopy (FTIR) and X-Ray Diffraction (XRD) which confirmed the accurate synthesis. The reduction of GO was validated by the disappearance of (OH) broad peak in the FTIR analysis. The rGO/UHMWPE nanocomposite was prepared by adding 0.7 wt.% of rGO employing the solvent mixing method. The morphology of the composite was validated by Scanning Electron Microscopy (SEM). Tensile and Izod Impact tests were performed on the samples which showed an increase in tensile strength of 33.2% and the impact strength increased by 140.5%. The rGO/UHMWPE nanocomposite with greater tensile and impact strength is an excellent candidate to produce orthopedic implants with superior properties.